A question about materials

I’m kind of old school, nearly everything I learned was from my father who passed when I was 17. I’m now 53 or 54, not sure which. I’ve just built some mobile stands for some tools I’ve acquired using the oddball methods I learned and am quite proud of how they look.

Ok, here the thing. When I was young and first learning particle/pressboard was invented. That one invention probably taught me every curse word and insult imaginable as my father described or encountered it Now there is a newer term “MDF” which i think is marketing for ours is better and don’t suffer the problems blah blah. It probably a good thing my dad died before OSB was invented, more curse words would have been invented.

This being said, I have to question, Why would anyone use such a inferior material when ply been around since the ancient Egyptians. Is there any merit to it. It is cheaper marginally, maybe.

The mobile stands I made which I will post about later were made with 3/4 CDX top and bottom and 1×2 framing. To make the CDX pretty my technique is unique. I cut them and than hit them hard with a putty knife and sheetrock joint compound to fill the pores and imperfections. Than I paint the mobile stands with porch and deck enamel. They not only look good but are very durable.

One of my upcoming projects though is a router table which will need veneering with Formica or some other laminate on the top. Most projects that do this seem to use the evil particleboard for this. Is there a reason?Does laminate not adhere to plywood? Or is it simply people being cheap.

High density particle board has been the standard for laminate counter tops since before I started in the trade 40 years ago. I feel it is superior to plywood for this purpose. Most products have a place where they perform well I would 10 times rather use Avantech floor sheathing over plywood here in the North East where it rains every day or two during construction season. Much of the CDX sheathing grade plywood sold is such poor quality I will not use it and cheap ain’t the reason for not using it. High quality is what I am after and if OSB, or MDF is the best product for the job I will be a SOB if I am going to use plywood.

-- A tube of calk and a gallon of paint will make a carpenter what he ain't

I too was raised old school and just mentioning partical board or MDF was curse words. I was taught that both were only used because it was cheap but they where inferior in quality compared to plywood.

It took me years doing woodworking professionally before I realized there were places and times when MDF was actually a better product to use ( no, not in fine furniture or fine cabinetry).

A couple of advantages using MDF versus plywood; if you are going to paint a project, you can eliminate the steps of having to fill the entire surface so you can sand it smooth. You can route a profile on MDF ( not so easy with plywood without blowout and a lot of filling voids).

MDF works great for doing raised panels for painted doors. (can’t do raised panels with plywood)

By no means do I think MDF is superior to a good grade plywood for most building purposes, but it’s not always a curse to use it. There’s definitely a time and place when MDF works well and it’s not always just because it’s cheaper.

Personally, I would much rather work with solid wood or a furniture grade plywood, but I do use MDF in certain instances and have slowly allowed myself to admitting it. LOL.

I have used a product call Extera, an exterior grade mdf for many projects. One of which was columns on a home.Product is very stable, weather resistant, strong and flat, but very heavy.In the shop…...jigs and fixtures, a dado fence for the ts, etc.A man made product such as ply and mdf, hdf, etc. has a place. Use it where appropriate.Bill

If you apply known techniques which you typically use on one material to an unknown material, there’s a fair chance failure, and epithets, will be in the air. It’s all a matter of proper tools and appropriate techniques.

Take varnish, which is known. You’ve seen Norm grab a foam brush and start spreading. Try that brush on lacquer…Failure! Is it the lacquer’s fault? Noop. Lacquer behaves differently from varnish.

Here on LJ we often hear, “I tried __ and it was awful and I’ll never use it again.” (ex: waterborne poly, polyurethane glue, hickory, hide glue, pine, etc. etc.)

Learn how your material behaves. Wisdom from George. And whiskers, the OP, has brought us a new way to deal with the surface of CDX: joint compound! How did he know to do that? I have a hunch he had learned, at some point, how joint compound behaves!

Kindly,

Lee

-- "...in his brain, which is as dry as the remainder biscuit after a voyage, he hath strange places cramm'd with observation, the which he vents in mangled forms." --Shakespeare, "As You Like It"

MDF and particle board are 2 very different animals. I like MDF for things like router tables for 2 reasons, one is flatness, and two is density. MDF is very heavy and dense and can absorb a lot of vibration. If you cover it w/ plastic laminate it makes a very durable surface.

Hallelujah Lee, it has always bugged me that the marketed woodworking world is so focused on teaching to the tool, but that is where the money is … I learned via materials and methods…. and lot of mistakes. MDF has it’s place and for what it is .. and it is really handy…. LDF is great for light weight bending forms and HDF is great for holding unusual shapes. Like Melamine, particle board, hard board, and plywood… it has it’s place in the wood shop, but not for all applications. My father taught me the basics as well… he also cursed a lot, and threw things… and was a hater of different materials….and I am still in therapy. (JK…LOL)

-- " 'Truth' is like a beautiful flower, unique to each plant and to the season it blossoms ... 'Fact' is the root and leaf, allowing the plant grow and bloom again."

I made my router table top by gluing two pieces of 3/4 MDF together with contact cement. Then I laminated white Formica over it and trimmed the edges with oak banding. So far (about a year) it has held up great.

Thanks for the good info so far. I sent a private message to the fellow who prompted my original questions cause he used what he called High quality particleboard (oxymoron?) for his router table and laminated on both the top and bottom which I thought was unusual, so I asked him why he chose that material and laminated on both sides. He said he had a cabinet shop make his top and that was what they used but if you glue 2 pieces of ply together they would warp, I’ve never heard that myself, but never tried it or heard of anyone who did. I would like to know if that is a no no cause that is just the type of crazy thing I might do if I had a couple thinner pieces of scrap and I wanted a thicker top or bottom out of them. He said MDF was more prone to swelling from moisture than particle board, which seemed also odd as I thought that was one of the advantages of MDF was it was more waterproof. The reason for laminateing both sides was moisture penetration from the bottom. On reflection, I think that would depend on where you live. Ludicrous idea in Arizona, but not so crazy for Florida, Houston, or N. Alabama where I live.

Thanks Lee for the comments about my novel use of joint compound. I have done a good bit of sheetrock work myself, so yes I know how it behaves. A few words about that. When doing wood, if your filling voids, it don’t really matter so it better to go ahead and take the stuff off the top of the can cause it tends to be dryer than what is inside the can, but when skimming the surface to fill pores, you want the wetter stuff that is covered up, it will suck in better and stick. For sanding get those screens made for the purpose. Sandpaper hates joint compound. Clogs it right up. Use the screens and they last a long time. Works just fine in my 30+ year old craftsman jitterbug. Important, Sand promptly. Wait til it completely dries of course, or you just clog up, but sand immediately. Usually within hours. Don’t wait a day. Joint compound cures and becomes super hard. Much easier to sand if you get to it when it first dries. And it don’t have to be perfectly smooth cause by definition your going to be painting it. You’ll actually save money cause the compound seals the wood so it don’t just suck up a ton of expensive primer necessitating extra coats. How did I learn to do this? Well I used to make models and they sold this expensive sealer stuff for balsa, which is kind of course wood, but you wanted a mirror smooth finish. I once had a cheap project I was doing that I really didn’t care that much about, But wanted it to look decent enough and thought about the sealer from than. Well they don’t make such a thing for construction wood and it just kind of hit me. I also joint compound to fill small cracks and voids. If you got something more major, like a thru knot hole in solid wood, I woudn’t use joint compound, I bought a can of automotive bondo which is a idea I got from one of you guys somewhere. Joint compound is great for filling those voids from missing knotholes on the bad side of CDX though. Really helps hide the fact your cheaped out on material when you open the cabinet. Just kind of a footnote for those who aren’t sure, how big a void/hole/crack can you fill? well joint compound isn’t the best thing for kreg pocket holes. It will shrink too much for that. Can be done, but you’ll have to hit it with a 2nd application of joint compound. Been there done that. That why I bought the bondo.